/**
 * Copyright (C) 2015 The Gravitee team (http://gravitee.io)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.gravitee.am.gateway.handler.common.vertx.web.handler.impl.internal;

import io.vertx.core.Handler;
import io.vertx.reactivex.ext.web.RoutingContext;

import java.util.Iterator;
import java.util.List;

/**
 * @author Titouan COMPIEGNE (titouan.compiegne at graviteesource.com)
 * @author GraviteeSource Team
 */
public class AuthenticationFlowChain {

    private final List<AuthenticationFlowStep> steps;
    private Iterator<AuthenticationFlowStep> stepsIterator;
    private Handler<Handler<RoutingContext>> exitHandler;

    public AuthenticationFlowChain(List<AuthenticationFlowStep> steps) {
        this.steps = steps;
        this.stepsIterator = steps.iterator();
    }

    public void doNext(RoutingContext routingContext) {
        if (stepsIterator.hasNext()) {
            AuthenticationFlowStep step = stepsIterator.next();
            step.execute(routingContext, this);
        } else {
            exitHandler.handle(nextHandler);
        }
    }

    public void exit(AuthenticationFlowStep step) {
        exitHandler.handle(step.handler());
    }

    void handle(RoutingContext routingContext) {
        doNext(routingContext);
    }

    public AuthenticationFlowChain exitHandler(Handler<Handler<RoutingContext>> exitHandler) {
        this.exitHandler = exitHandler;
        return this;
    }

    private Handler<RoutingContext> nextHandler = routingContext -> routingContext.next();
}
